Method and base station for transmitting a data block

ABSTRACT

A method and a base station of transmitting a data block are provided. At least one data block is transmitted via at least one of at least two downlink frequency bands. A modulation symbol and N spreading sequences are received. Acknowledgement/negative acknowledgement (A/N) information is determined in accordance with the modulation symbol and the N spreading sequences. The modulation symbol and the N spreading sequences jointly determine the A/N information. And the at least one data block may be retransmitted depending on the A/N information determined.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is continuation of U.S. patent application Ser. No.14/323,482, filed on Jul. 3, 2014, which is a continuation of U.S.patent application Ser. No. 13/175,548, filed on Jul. 1, 2011, now U.S.Pat. No. 8,804,638. U.S. patent application Ser. No. 13/175,548 is acontinuation of International Patent Application No. PCT/CN2009/075581,filed on Dec. 15, 2009, which claims priority to Chinese PatentApplication No. 200910076433.4, filed on Jan. 4, 2009. Theafore-mentioned patent applications are hereby incorporated by referencein their entireties.

TECHNICAL FIELD

The present application relates to the field of wireless communicationstechnologies, and in particular, to a method and a user equipment (UE)for transmitting multiple A/N information.

BACKGROUND

A Hybrid Automatic Retransmission Request (HARQ) is a mechanism forimproving the performance of a wireless communication system. On adownlink of the system, an application process of the HARQ is describedas follows: A base station (BS) first sends a data block and controlinformation related to the data block to a certain user; after correctlyreceiving the control information, the user checks the data blockcorresponding to the control information. If the check result iscorrect, an acknowledgement (ACK) is sent to the BS; after receiving theACK, the BS regards that the data block is received by the correspondinguser correctly, so a new data block can be sent to the user. If thecheck result is incorrect, the user sends a negative acknowledgement(NACK) to the BS; the BS re-transmits the sent data block to the useruntil the user returns ACK after correctly receiving the data block, oruntil the maximum re-transmission number is exceeded. In addition, ifthe user does not correctly receive the control information related tothe data block, the user does not detect the data block or return thecorresponding ACK or NACK on an uplink, so the user enters aDiscontinuous Transmission (DTX) state. The BS knows that the user is inthe DTX state through energy detection; at this time, the BS re-sendsthe data block and the control information.

In a 3rd Generation Partnership Project (3GPP) Long TermEvolution-Advanced (LET-A) Frequency Division Duplex (FDD) system, inorder to support a wider system bandwidth, multiple frequency bands aresupported simultaneously, which means spectrum aggregation, and datablocks are transmitted in every frequency band. For the data blocktransmitted in each downlink frequency band, the user needs to return acorresponding ACK or NACK, or enter the DTX state (which is referred toas returning an A/N/DTX in brief). It means that the user needs toreturn a plurality of A/N/DTXs in the uplink frequency bands. In a 3GPPLTE Time Division Duplex (TDD) system, downlink data is usuallytransmitted by multiple consecutive sub-frames. Referring to FIG. 13,the BS sends data blocks in multiple downlink sub-frames to a user, andin an uplink sub-frame, the user returns the A/N/DTX for the data blockin each downlink sub-frame, which means that a plurality of A/N/DTXsneeds to be returned in one sub-frame. In the existing 3GPP LTE TDDsystem, an A/N bundling method is used, that is to say, only one A/N isobtained after a logical AND operation on the A/N of each downlinksub-frame, and then the A/N is sent in an uplink sub-frame. In thebundling process, the DTX is regarded as a NACK.

SUMMARY

During the implementation of the embodiments of the disclosure, theinventors find that the prior art has at least the following problems:since a logical AND operation is used, when a transmission error occursin one of multiple sub-frames, an A/N feedback obtained by a BS is aNACK. However, the BS cannot determine, according to the received NACK,in which sun-frame the error occurs. Therefore, the data in allsub-frames needs to be re-transmitted, which decreases the systemtransmission efficiency and throughput.

An embodiment of the disclosure provides a method for transmittingmultiple A/N information, where the method includes: determiningreserved resources; determining A/N information that needs to betransmitted; determining N transmission resources and correspondingmodulation symbols according to the number of the reserved resources andthe A/N information that needs to be transmitted, where N is an integergreater than or equal to 2; and transmitting the modulation symbols byusing the transmission resources.

An embodiment of the disclosure provides a UE, where the UE includes: amodule, configured to determine reserved resources; a module, configuredto determine A/N information that needs to be transmitted; a module,configured to jointly select N transmission resources and correspondingmodulation symbols according to the number of the reserved resources andthe A/N information that needs to be transmitted; where N is an integergreater than or equal to 2; and a module, configured to transmit themodulation symbols by using the transmission resources.

An embodiment of the disclosure provides a UE, where the UE includes:

a first determination module, configured to determine reservedresources;

a second determination module, configured to determine A/N informationthat needs to be transmitted;

a grouping module, connected to the first determination module and thesecond determination module, and configured to divide bits of the A/Ninformation that needs to be transmitted into a first bit group and asecond bit group according to the number of the reserved resources, anddetermine that the number of transmission resources is N;

an obtaining module, connected to the grouping module, and configured toobtain N transmission resources from the reserved resources according tothe first bit group, and obtain the corresponding modulation symbolsaccording to the second bit group; and

a transmission module, connected to the grouping module and theobtaining module, and configured to transmit the modulation symbols byusing the transmission resources.

In the embodiment of the disclosure, N transmission resources and thecorresponding modulation symbols are obtained according to the number ofthe reserved resources and the A/N information that needs to betransmitted, where N is an integer greater than or equal to 2. In thismanner, multiple A/N information that needs to be transmitted isconveyed by the selected multiple transmission resources and modulationsymbols, and therefore, multiple A/N information can be transmittedsimultaneously. A BS can accurately know whether data block transmissionin each downlink frequency band is correct, thereby accuratelypositioning the downlink frequency band where an error occurs, so as toreduce unnecessary re-transmission caused by the A/N bundling manner inthe prior art. The A/N information includes ACK information, NACKinformation or DTX state information.

In addition, in the embodiment of the disclosure, the bits of the A/Ninformation that needs to be transmitted are divided into the first bitgroup and the second bit group. The transmission resources are obtainedfrom the reserved resources according to the first bit group, and thecorresponding modulation symbols are obtained according to the secondbit group. Then the modulation symbols obtained from the second bitgroup are transmitted through the multiple transmission resourcesobtained according to the first bit group. In this manner, multiple A/Ninformation that needs to be transmitted are conveyed by the selectedmultiple transmission resources and modulation symbols, and thereforemultiple A/N information can be transmitted simultaneously. The BS canaccurately know whether data block transmission in each downlinkfrequency band is correct or not, thereby accurately positioning thedownlink frequency band where an error occurs, so as to reduceunnecessary re-transmission caused by the A/N bundling manner in theprior art.

In addition, in an embodiment of the disclosure, multiple transmissionresources can be transmitted by using the multi-antenna technology, thatis, each antenna sends a transmission resource, and the transmissionresources on different antennas can carry the same or differentmodulation symbols. In this manner, each antenna can ensuresingle-carrier transmission and further obtain a transmission diversitygain and spatial multiplexing gain of the multiple antennas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a resource block of a Physical UplinkControl Channel (PUCCH) according to an embodiment of the disclosure;

FIG. 2 is a schematic structural diagram showing the sending of an A/Naccording to another embodiment of the disclosure;

FIG. 3 is a schematic diagram of a mapping relationship between a PacketData Control Channel (PDCCH) and a Control Channel Element (CCE)according to another embodiment of the disclosure;

FIG. 4 is a schematic diagram of a mapping relationship between anuplink and a downlink according to another embodiment of the disclosure;

FIG. 5 is a schematic flowchart of a method according to anotherembodiment of the disclosure;

FIG. 6 is a schematic diagram showing the sending of sequences andsymbols of a UE according to another embodiment of the disclosure;

FIG. 7 is a schematic diagram showing the sending of sequences andsymbols of a UE according to another embodiment of the disclosure;

FIG. 8 is a schematic diagram showing the sending of sequences andsymbols of a UE according to another embodiment of the disclosure;

FIG. 9 is a schematic diagram showing the sending of sequences andsymbols of a UE according to another embodiment of the disclosure;

FIG. 10 is a schematic diagram showing the sending of sequences andsymbols of a UE according to another embodiment of the disclosure;

FIG. 11 is a schematic diagram of a mapping relationship between anuplink and a downlink according to another embodiment of the disclosure;

FIG. 12 is a schematic structural diagram of a UE according to anotherembodiment of the disclosure; and

FIG. 13 is a method for transmitting multiple pieces of A/N informationin the prior art.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The details such as specific architectures, interfaces, and techniquesin the following description are used to illustrate the embodiments ofthe disclosure for a thorough understanding, and are not intended tolimit the scope of the present application. It is clear to personsskilled in the art that the disclosed embodiments can also beimplemented in other embodiments departing from these specific details.In other cases, detailed descriptions for well-known devices, circuitsand methods are omitted in case that unnecessary detail affects theillustration of the embodiments. In addition, functional blocks areprovided in some drawings. It should be understood by persons skilled inthe art that these functions can be implemented through an independenthardware circuit, a digital microprocessor combining proper programmingor software for general computer operating, an application-specificintegrated circuit (ASIC) and/or one or more digital signal processors(DSPs).

The term UE in the embodiments of the disclosure includes, but is notlimited to, a mobile station, a UE, fixed or mobile subscriber unit, afax, a wireless phone, a personal digital assistant (PDA), a computer orother types of UE that can work in a wireless environment. The term BSin the embodiments of the disclosure includes but is not limited to aBS, an eNB, a Node B, a station controller, an access point (AP), orother types of equipment that can work in the wireless environment andinteract with the preceding UE.

The technical solutions of the disclosure are further described in thefollowing through the drawings and embodiments.

In the embodiments of the disclosure, when a BS (eNB) sends a data blockand a related control signaling to a UE in a downlink, assuming that thecontrol signaling is received correctly, the UE returns a correspondingA/N to the eNB in a PUCCH according to whether a check for the datablock is correct or not. If the control signaling is not receivedcorrectly, the UE is in a DTX state, which means that the UE does notsend anything. The PUCCH performs transmissions in two time slots of asub-frame, where the PUCCH includes multiple resource blocks. Eachresource block occupies 12 consecutive sub-carriers on a frequencydomain, and occupies 6 or 7 symbols on a time domain. The number ofsymbols occupied by a resource block on the time domain is relevant tothe length of a cyclic prefix. In a normal cyclic prefix, 7 symbols areoccupied; and in an extended cyclic prefix, 6 symbols are occupied. Thefollowing discussion is based on the assumption that a resource blockoccupies 7 symbols. A/Ns of a user are transmitted in two resourceblocks of the PUCCH, where the two resource blocks are located indifferent time slots. The resource block in the second time slot repeatsdata of the first resource block. FIG. 1 is a schematic diagram of aresource block of a PUCCH according to an embodiment of the disclosure.Referring to FIG. 1, in a resource block for transmitting A/Ns, 3symbols are used to transmit demodulation pilot, and the remaining 4symbols are used to transmit the A/Ns.

In a resource block of the PUCCH, A/Ns of different users aremultiplexed through code division, where codes of different users areorthogonal to distinguish different users. The A/N of each user isgenerally a Binary Phase Shift Keying (BPSK) or a Quadrature Phase ShiftKeying (QPSK) symbol. If the user only has one codeword (or transmissionblock) in the downlink, the A/N of only 1 bit is required; at this time,the A/N is a BPSK symbol. If the user has two code words in thedownlink, that is, Multiple Input Multiple Output (MIMO) is used, and itis required that the A/N of two bits corresponds to two code words,respectively. At this time, the two A/N bits are modulated into a QPSKsymbol. This modulation symbol (BPSK or QPSK) is mapped onto theresource block shown in FIG. 1 after spreading. A sequence used in thespreading is a two-dimensional orthogonal spreading code. The spreadingcode in the frequency domain is a sequence with the length of 12, andaltogether 12 different sequences exist; the spreading code in the timedomain is a orthogonal sequence with the length of 4, and altogether 3different sequences exist. The 12 sequences on the frequency domain areobtained through phase rotation of a basic sequence, that is,r^(α)(n)=e^(j2πnα)r(n), n=0, 1, Λ, 11; α=0, 1, Λ, 11, where r(n)represents the basic sequence with the length of 12, and r^(α) (n)represents a sequence obtained after the phase rotation of the basicsequence. The 3 quadrature sequences with the length of 4 exist on thetime domain, as shown in Table 1.

TABLE 1 Sequence number β [w(0) w(1) w(2) w(3)] 0 [1 1 1 1] 1 [1 −1 1−1] 2 [1 −1 −1 1]

FIG. 2 is a schematic structural diagram showing the sending an A/Naccording to another embodiment of the disclosure. Referring to FIG. 2,a modulation symbol m corresponding to an A/N of a user is mapped into 4A/N symbols in a resource block after two-dimensional spreading of timedomain and frequency domain sequences. The frequency domain sequenceused is r^(α)(n), and the sequence used in the time domain is w^(β)(n).FIG. 2 may include 36 pilots at most for selection, and may support 36users at most.

A resource block includes 12 sequences in the frequency domain, and 3sequences in the time domain, and therefore has 36 sequencecombinations, namely 36 two-dimensional spreading sequences. All userstransmitting A/Ns in a same resource block use different sequences inthe 36 two-dimensional spreading sequences. Referring to Table 2, the 36two-dimensional spreading sequences can be numbered by K as follows.

TABLE 2 Frequency domain Time domain sequence number sequence number 0 12 0 K = 0 K = 12 K = 24 1 K = 1 K = 13 K = 25 2 K = 2 K = 14 K = 26 3 K= 3 K = 15 K = 27 4 K = 4 K = 16 K = 28 5 K = 5 K = 17 K = 29 6 K = 6 K= 18 K = 30 7 K = 7 K = 19 K = 31 8 K = 8 K = 20 K = 32 9 K = 9 K = 21 K= 33 10 K = 10 K = 22 K = 34 11 K = 11 K = 23 K = 35

In some specific channel conditions, for example, a channel with strongfrequency selectivity, only 6 sequences of the 12 sequences in thefrequency domain can be used, and one sequence exists between twofrequency domain sequences. In this manner, 18 two-dimensional spreadingsequences can be generated. Referring to Table 3, the 18 sequences canbe numbered as follows:

TABLE 3 Frequency domain Time domain sequence number sequence number 0 12 0 K = 0 K = 12 1 K = 6 2 K = 1 K = 13 3 K = 7 4 K = 2 K = 14 5 K = 8 6K = 3 K = 15 7 K = 9 8 K = 4 K = 16 9 K = 10 10 K = 5 K = 17 11 K = 11

When transmitting the A/N in the PUCCH, the user needs to select atwo-dimensional spreading sequence K, and obtain a correspondingfrequency domain spreading sequence and time domain spreading sequenceaccording to K to send the A/N by using the selected spreadingsequences. A process for the user to obtain the required K is describedbelow.

When the eNB transmits the data block to the user, a PDCCH istransmitted to instruct at which resource block the data block of theuser is located, as well as the control signaling such as a modulationcoding manner and a precoding matrix used in the transmission. Thecontrol signaling is the above mentioned control signaling related tothe transport block. The user first detects the PDCCH; if the PDCCH isdetected, the transmitted data block is demodulated according tocontents instructed by the PDCCH. For dynamically scheduled users, eachuser has a PDCCH. A PDCCH is formed by 1, 2, 4 or 8 CCEs. The number ofCCEs of a PDCCH is relevant to the size of the control signalingcontents and channel quality of the user. For example, if the channelquality of a user is poor, in order to improve the performance of thePDCCH, 8 CCEs are used to transmit the PDCCH of the user. At this time,a low coding bit rate is used in the PDCCH of the user to resist thefading of the channel.

FIG. 3 is a schematic diagram of a mapping relationship between a PDCCHand a CCE according to another embodiment of the disclosure. Referringto FIG. 3, altogether four users are involved; each user corresponds toone PDCCH, and the four PDCCHs are respectively a first PDCCH, a secondPDCCH, a third PDCCH, and a fourth PDCCH. The first PDCCH and the secondPDCCH each includes one CCE, that is, the first PDCCH includes a firstCCE and the second PDCCH includes a second CCE; the third PDCCH includestwo CCEs (a third CCE and a fourth CCE); and the fourth PDCCH includesfour CCEs (a fifth CCE, a sixth CCE, a seventh CCE, and an eighth CCE).

The two-dimensional spreading sequence K that the user uses to returnthe A/Ns is determined by the location of the first CCE of the PDCCH ofthe user. A start CCE of each user PDCCH is different, and therefore,different two-dimensional spreading sequences K can be determined. In aword, the K and the start CCE of the PDCCH can share a fixedrelationship, which is not described in detail herein. It is assumedthat K=N_(index of first CCE)+4, so:

user 1: K=0+4=4

user 2: K=1+4=5

user 3: K=2+4=6

user 4: K=4+4=8

Then, the frequency domain sequence and the time sequence of the sentA/N can be obtained according to the mapping relationship between thenumber K of the two-dimensional spreading sequence and the time andfrequency sequences, for example, Table 2, Table 3 or other similartables (it is determined according to the specific channel conditionswhether to use Table 2, Table 3 or other similar tables). According tothe mapping relationship in Table 2, user 2 uses the 5^(th) frequencydomain sequence and the 1^(st) sequence of the time domain. It can beseen from the above that K=7 will not be used by other users, since theCCEs corresponding to K=7 are occupied by the PDCCH of user 3,indicating that user 3 can actually use 2 two-dimensional spreadingsequences, that is, the user corresponds to M CCEs, which indicates thatM two-dimensional spreading sequences can be used.

The LTE-A system supports users to transmit data by using multipledownlink frequency bands or uplink frequency bands at the same time; inthis way, users can use a wider bandwidth to transmit data. The multiplefrequency band transmission is a main characteristic of the LTE-Asystem; however, this characteristic also causes some problems. Whenreceiving the downlink data, a user cannot exactly know in whichfrequency bands the eNB transmits data to the user; therefore, the userneeds to constantly detect whether each frequency band includes the datato be transmitted to the user, which results in high power consumption.

In order to reduce the power consumption of users, a main downlinkfrequency band is defined for each user; a corresponding signaling istransmitted in the primary downlink frequency band to instruct whetherdata is transmitted in downlink frequency bands other than the primarydownlink frequency band. The primary downlink frequency bands ofdifferent users may be different. For example, altogether 3 downlinkfrequency bands exist in the system, which respectively are frequencyband 1, frequency band 2, and frequency band 3; then, frequency band 1,frequency band 2, and frequency band 3 can be defined as the primarydownlink frequency bands of user 1, user 2, and user 3. After theprimary downlink frequency band is defined, each user first detectswhether the primary downlink frequency band includes data that the userneeds to receive, and then determines whether to detect other downlinkfrequency bands according to the signaling received in the main downlinkfrequency band. If the primary downlink frequency band instructs that nodata is transmitted in other frequency bands, the user does not need todetect other sub-frequency bands; if the primary downlink frequency bandinstructs that data is transmitted in other frequency bands, the userdetects the data in a specified frequency band, so that unnecessarydetection is avoided. Similarly, when the user transmits data in theuplink, if the data that needs to be sent to the eNB is not much, thedata does not need to be always sent on multiple sub-frequency bands,and may be sent only in a primary uplink frequency band. In this manner,for each user, the primary downlink frequency band and the primaryuplink frequency band constitute a pair of primary frequency bands.

When data blocks are transmitted to a certain user in multiple downlinkfrequency bands, the user needs to return an A/N for the data blocktransmitted in each downlink frequency band, and therefore the number ofthe A/Ns that need to be returned is relevant to the number of thedownlink frequency bands used. The multiple A/Ns are sent in the primaryuplink frequency band of the user. For example, the system includesthree downlink frequency bands and two uplink frequency bands, which arerespectively downlink frequency band 1, downlink frequency band 2,downlink frequency band 3, uplink frequency band 1, and uplink frequencyband 2. The downlink frequency band 1 and uplink frequency band 1 aredefined as the primary frequency band pair of the user 1. The downlinkfrequency band 2 and uplink frequency band 2 are defined as the primaryfrequency band pair of the user 2. If data is transmitted to user 1 anduser 2 in all three downlink frequency bands, both user 1 and user 2return A/Ns on the primary uplink frequency band of each respectively.

FIG. 4 is a schematic diagram of a mapping relationship between anuplink and a downlink according to another embodiment of the disclosure.Referring to FIG. 4, a Physical Downlink Shared Channel (PDSCH)i-jrepresents transmission of a data block to a jth user on an ith downlinkfrequency band.

FIG. 5 is a schematic flow chart of a method according to anotherembodiment of the disclosure, which includes the following steps.

In Block 51, a UE determines reserved resources. The reserved resourcesand transmission resources involved herein may be time, frequencies,codes, sequences, antennas, and so on. The reserved resources andtransmission resources being sequences is taken as an example below.

According to the preceding analysis, in order to avoid unnecessarydetection, a BS usually transmits a data block of a user on a maindownlink frequency band of the user. While in the preceding descriptionof the sequence, it can be understood that the number of the sequencesused in an uplink frequency band is the same as the number of CCEs forthe user in a PDCCH of the corresponding downlink frequency band.Therefore, the number of the CCEs included in the PDCCH of the primarydownlink frequency band of the user may be selected as the number of thereserved resources. For example, if the PDCCH of the primary downlinkfrequency band of the user includes M CCEs, the number of the reservedresources is M. Besides, based on the relationship between the CCE andthe sequence, the reserved resources of the user can be obtainedaccording to the CCE corresponding to the user (for example, thereserved resources can be obtained according to a relationship betweenthe start location of the CCE and a sequence K).

In another situation, a downlink frequency band set is defined for eachuser. Different users can have the same or different downlink frequencyband sets. A data block and a corresponding PDCCH for each user can besent in at least one frequency band in the downlink frequency band setcorresponding to the user. The downlink frequency band of each user caninclude a part of or all of the downlink frequency bands. In thismanner, when receiving downlink data, the user needs to perform PDCCHdetection on each downlink frequency band in the downlink frequency bandset, and demodulate a transmission block according to a result of thePDCCH detection. In this case, every downlink frequency band may havethe PDCCH.

Of course, if the data of the user is sent to the user in multipledownlink frequency bands, and each downlink frequency band carries thePDCCH for the user, the number of the reserved resources may also be thetotal number of the CCEs included in the PDCCHs of the downlinkfrequency bands corresponding to the user. For example, the BS transmitsthe data blocks to the user in downlink frequency band 1 and downlinkfrequency band 2, where the PDCCH of downlink frequency band 1 includesM1 CCEs, and downlink frequency band 2 includes M2 CCEs; then the numberof the reserved resources is M=M1+M2. The reserved resources obtainedaccording to the CCEs included on the primary downlink frequency bandare taken as an example below.

The preceding reserved resources are all obtained indirectly accordingto the PDCCH; of course, the reserved resources may also be assigned bythe BS explicitly, for example, assigned explicitly through a higherlayer signaling in a semi-static state manner or through a dynamicsignaling. Further, the reserved resources may be a combination of theexplicit assignment and indirect assignment, for example, the reservedresources may be obtained indirectly through the PDCCH and explicitlythrough the higher layer signaling.

After the reserved resources are determined, N resources of the Mreserved resources can be selected as transmission resources, where N isa number from 1 to M−1.

In Block 52, the UE determines A/N information that needs to betransmitted.

Specifically, A/N information corresponding to codewords included ineach downlink frequency band is bundled respectively, that is, the “AND”operation is performed on the A/Ns of each downlink frequency band.After the logic AND operation, only one A/N is obtained, therebyobtaining the A/N information that needs to be transmitted correspondingto each downlink frequency band. Alternatively, the A/N informationcorresponding to the codewords included in each downlink frequency bandis used as the A/N information that needs to be transmitted, therebyobtaining the A/N information that needs to be transmitted correspondingto each codeword. For example, if the number of the downlink frequencybands is 4, and each downlink frequency band includes 2 codewords,altogether 8 bits of the A/N information exist. If it is determined thatthe 8-bit A/N information is too much according to conditions of thereserved resources, transmission resources, and modulation symbols, forinstance, the number of the reserved resources is 4; the number of thetransmission resources is 2; and the modulation symbols are QPSKsymbols, which means that only 2 bits are required for instructing thetransmission resources, 4 bits at most are required for instructing themodulation symbol, and the remaining 2 bits fail to characterize theinformation of the transmission resources or modulation symbols. Thenthe logic AND operation can be performed on two A/Ns of each downlinkfrequency band to obtain 4-bit A/N information. When the performance ofthe system is capable of transmitting 8 bits, the 8 bits can be directlyused as the number of bits of the A/N information that needs to betransmitted.

If the user does not know the number of PDCCHs transmitted from the BSin the downlink frequency band, the number of the PDCCHs correctlyreceived by the user may be smaller than the number of the PDCCHs sentby the BS. For example, for a specific user, the BS sends a PDCCHrespectively in each of the three downlink frequency bands. It isassumed here that each PDCCH corresponds to a data block. However, at areceiving end, the user only correctly receives two PDCCHs; then theuser regards that the BS only sends two PDCCHs and two data blocks, andonly returns A/Ns for the two data blocks in an uplink PUCCH.

In another situation, the user knows the number of the PDCCHstransmitted from the BS in the downlink frequency bands; at this time,the number of the A/Ns returned by the user in the uplink PUCCH is equalto the number of the PDCCHs. For example, a user knows that the BS sendstwo PDCCHs in the downlink frequency bands, and each PDCCH correspondsto a data block. However, if only one PDCCH is correctly detected at thereceiving end, the user regards that the other PDCCH is not detectedcorrectly. At this time, the user returns the A/N in the uplink for thedata block corresponding to the correctly received PDCCH, and returns aDTX for the data block corresponding to the PDCCH that is not correctlyreceived; at this time, the feedback information is (A/N, DTX).

In Block 53, the UE divides the A/N information that needs to betransmitted into a first bit group and a second bit group according tothe number of the reserved resources, and determines that the number ofthe transmission resources is N.

Specifically, the bit number m1 of the first bit group can be determinedaccording to the number M of the reserved resources and the number N ofthe transmission resources, where 2^(m1)≦C_(M) ^(N). The bit number m2of the second bit group can be obtained according to the bit number m ofthe A/N information that needs to be transmitted and the bit number m1of the first bit group, where m2=m−m1. For example, if M=4, and N=2,then m1 can be selected as 1 or 2 (according to actual configurationrequirements). After that, it is obtained that m2=m−m1.

For example, the reserved resources are 4 sequences, namely, S1, S2, S3,and S4; the A/N that needs to be transmitted is 4-bit information,namely A/N(0), A/N(1), A/N(2), and A/N(3); and it is determined that thenumber of the transmission resources is 2, namely two transmissionsequences. Then, the 4-bit A/N information that needs to be transmittedcan be divided into two groups, namely [A/N(0), A/N(1)] and [A/N(2),A/N(3)], where the group [A/N(0), A/N(1)] is used for selecting twotransmission sequences among four sequences, and the group [A/N(2),A/N(3)] is used for modulating a QPSK symbol, as shown in the followingtable.

TABLE X-1 A/N (1) A/N (2) (S1, S2) (S1, S3) (S1, S4) (S2, S3) 00 ✓ 01 ✓10 ✓ 11 ✓

TABLE X-2 A/N(3)A/N(4) QPSK modulation symbol 00$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 01 $Q_{1} = \frac{1 - j}{\sqrt{2}}$ 10$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 11$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$

If Table X-1 and Table X-2 are combined, that is, the transmissionsequence and the modulation symbol are jointly selected by using[A/N(1)A/N(2)A/N(3) A/N(4)], a mapping relationship can be obtained asshown in Table X-3.

TABLE X-3 A/N(1)A/N(2)A/N(3) A/N(4) Sequence Modulation symbol 0000 (S1,S2) $Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0001 (S1, S2)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 0010 (S1, S2)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 0011 (S1, S2)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 0100 (S1, S3)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0101 (S1, S3)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 0110 (S1, S3)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 0111 (S1, S3)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1111 (S1, S4)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 1000 (S1, S4)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1110 (S1, S4)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 1011 (S1, S4)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1001 (S2, S3)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 1100 (S2, S3)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1010 (S2, S3)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 1101 (S2, S3)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$

By comparing Table X-1 and Table X-2 with Table X-3, it is easy toconclude that Table X-3 is based on the same idea, solves the sametechnical problem, and brings the same technical effect as Table X-1 andTable X-2. Therefore, specifically, the second bit group can be empty,namely m2=0, and m1=m. More specifically, no A/N information includesthe DTX.

Alternatively, the A/N information that needs to be transmitted includesthe DTX.

In Block 54, the UE determines N transmission resources from thereserved resources according to the first bit group, and determines thecorresponding modulation symbols according to the second bit group.

Specifically, when the second bit group is empty, the UE also obtainsthe N transmission resources from the reserved resources and themodulation symbols according to the A/N information of the first bitgroup.

In Block 55, the UE transmits the determined modulation symbols by usingthe determined transmission resources.

The transmission methods of the disclosure are described through thefollowing embodiments with different transmission resources (thesequence may be taken as an example) and different modulation symbols(the QPSK may be taken as an example).

In Mode 1, the UE includes only one antenna, and the antenna transmitsone sequence. The sequence transmits one modulation symbol. It isassumed that 2 downlink frequency bands transmit data to the user, andeach downlink frequency band includes two codewords. The PDCCH of themain downlink frequency band is formed by 4 CCEs. Then 4 sequences (M=4)are reserved in the primary uplink frequency band (namely the number ofthe reserved resources). The sequences are S1, S2, S3 and S4respectively (namely the reserved resources). It is assumed that Ntransmission sequence needs to be selected (N=1); then the transmissionresource is S1, S2, S3 or S4. The number of bits of the A/N informationthat needs to be transmitted is 4 (m=4), and the A/N information is A/N(1), A/N (2), A/N (3) and A/N (4) respectively. The bits, of which m=4,are divided into two parts: a first bit group [A/N(1) A/N(2)], of whichm1=2, and a second bit group [A/N(3) A/N(4)], of which m2=m-m1=2. Thetransmission sequence which selects N=1 in the reserved sequences isobtained according to the first bit group [A/N (1) A/N (2)], and themodulation symbol is obtained according to the second bit group [A/N (3)A/N (4)]. For the relationship between the first bit group and thetransmission sequence, references can be made to Table 4. For therelationship between the second bit group and the modulation symbol(QPSK symbol), references can be made to Table 5.

TABLE 4 A/N (1) A/N (2) S1 S2 S3 S4 00 ✓ 01 ✓ 10 ✓ 11 ✓

TABLE 5 A/N(3) A/N(4) QPSK Symbol 00 $Q_{0} = \frac{1 + j}{\sqrt{2}}$ 01$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 10 $Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$11 $Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$

FIG. 6 is a schematic diagram showing the sending of sequences andsymbols according to another embodiment of the disclosure. Referring toFIG. 6, after a transmission sequence Si and a QPSK symbol are obtainedby referring to Table 4 and Table 5 according to the bits of the A/Ninformation that needs to be transmitted, the sequence is sent throughan antenna of the system, and the QPSK symbol is transmitted in thesequence. For example, for a user, when A/N(1)=1, A/N(2)=0, A/N(3)=0,and A/N(4)=1, then the transmission sequence obtained according to Table4 is S3; the QPSK modulation symbol obtained according to Table 5 is Q1.After that, Q1 is sent through the antenna through the S3 sequence. TheBS performs the detection after receiving a feedback signal, and the BSdetects that the Q1 is sent in the S3. Further, the BS can obtain[A/N(1) A/N(2)]=[1 0], [A/N(3) A/N(4)]=[0 1] according to thecorresponding relationships in Table 4 and Table 5. When the A/N is 1,it indicates correct transmission, and when the A/N is 0, it indicatesincorrect transmission. Besides, during the negotiation with a terminal,the BS knows in advance that A/N(1), A/N(2), A/N(3) and A/N(4)respectively correspond to a first codeword of a first downlinkfrequency band, a second codeword of the first downlink frequency band,a first code word of a second downlink frequency band, and a second codeword of the second downlink frequency band. Therefore, the BS can knowthat the second codeword of the first downlink frequency band and thefirst codeword of the second downlink frequency band are transmittedincorrectly. The BS can re-transmit the second codeword of the firstdownlink frequency band and the first codeword of the second downlinkfrequency band only, and does not need to re-transmit all code words ofall frequency bands.

In Mode 2, the UE includes only one antenna, and the antenna transmitsmultiple sequences; the multiple sequences transmit different modulationsymbols. It is assumed that 3 downlink frequency bands transmit data tothe user, and each downlink frequency band includes two codewords. ThePDCCH of the main downlink frequency band is formed by 4 CCEs. 4sequences are reserved on the primary uplink frequency band (M=4), andthe sequences are S 1, S2, S3 and S4 respectively. It is assumed that 2transmission sequences need to be selected (N=2). Then the number ofbits of the A/N information that needs to be transmitted is 6 (m=6), andthe A/N information is A/N (1), A/N (2), A/N (3), A/N (4), A/N (5) andA/N (6) respectively. The bits, of which m=6, are divided into twoparts: a first bit group [A/N(1) A/N(2)], of which m1=2, and a secondbit group [A/N(3) A/N(4) A/N(5) A/N(6)], of which m2=m−m1=4. Thetransmission sequences which select N=2 in the reserved sequences areobtained according to the first bit group [A/N (1) A/N (2)], and twomodulation symbols are obtained according to [A/N (3) A/N (4)] and[A/N(5) A/N(6)] of the second bit group. For the relationship betweenthe first bit group and the transmission sequence, references can bemade to Table 6. For the relationship between the second bit group andthe modulation symbol (QPSK symbol), references can be made to Table 5.

TABLE 6 A/N(1)A/N(2) (S1,S2) (S1,S3) (S1,S4) (S2,S3) (S2,S4) (S3,S4) 00✓ 01 ✓ 10 ✓ 11 ✓

FIG. 7 is a schematic diagram showing the sending of sequences andsymbols according to another embodiment of the disclosure. Referring toFIG. 7, after transmission sequences Si and Sj, and QPSK symbols a1 anda2 are obtained through referring to Table 6 and Table 5 according tothe bits of the A/N information that needs to be transmitted, the twosequences are sent through an antenna of the system, and one QPSK symbolis transmitted in each sequence. For example, for a user, if A/N(1)=0,A/N(2)=1, A/N(3)=1, A/N(4)=0, A/N(5)=1, and A/N(6)=1, then thetransmission sequences obtained according to Table 6 and correspondingto [A/N(1),A/N(2)]=[0 1] are (S1, S3); the first QPSK modulation symbola1 obtained according to Table 5 and modulated based on[A/N(3),A/N(4)]=[1 0] is Q2; and the second QPSK modulation symbol a2obtained according to Table 5 and modulated based on [A/N(5),A/N(6)]=[11] is Q3. After that, different modulation symbols are respectivelymapped to different sequences, for example, the a1 is mapped to the Si,and the a2 is mapped to the S2. Then, two sequences transmitting themodulation symbols are sent through one antenna after being added, thatis, two sequences are modulated to one antenna. After receiving thefeedback signal, the BS performs the detection, and detects that thesequences (S1, S3) include the modulation symbols, and that the twomodulation symbols are Q2 and Q3 respectively. The BS can obtain [A/N(1)A/N(2)]=[0 1], [A/N(3) A/N(4)]=[1 0], and [A/N(5) A/N(6)]=[1 1]according to the mapping relationship between the transmission sequenceand the modulation symbol, and of Table 6 and Table 5. When the A/N is1, it indicates the correct transmission, and when the A/N is 0, itindicates the incorrect transmission. Besides, during negotiation withthe terminal, the BS knows in advance that A/N(1), A/N(2), A/N(3),A/N(4), A/N(5) and A/N(4) respectively correspond to a first code wordof a first downlink frequency band, a second code word of the firstdownlink frequency band, a first code word of a second downlinkfrequency band, a second code word of the second downlink frequencyband, a first code word of a third downlink frequency band, and a secondcode word of the third downlink frequency band. Therefore, the BS canknow that the first code word of the first downlink frequency band andthe second code word of the second downlink frequency band aretransmitted incorrectly. The BS can re-transmit the first code word ofthe first downlink frequency band and the second code word of the seconddownlink frequency band only, and does not need to re-transmit all codewords of all frequency bands.

In Mode 3, the UE includes multiple antennas, and each antenna transmitsone of multiple transmission sequences obtained. The multiple sequencesrespectively transmit different modulation symbols.

If each antenna sends one transmission sequence, a sending mode of thetransmission sequence through each antenna is the same as a transmissionmode of the LTE PUCCH, thereby ensuring single-carrier transmissionthrough each antenna. The single-carrier transmission has a lower Peakto Average Power Ratio (PAPR), or Cubic Metric (CM), so as to facilitatethe design of power amplifiers. Since each antenna sends one modulationsymbol, multiple antennas can send multiple modulation symbolssimultaneously. In this manner, a spatial multiplexing technology ofmultiple antennas is employed, so the system capacity is increased.

For example, this mode uses the same condition as assumed in Mode 2. Inthe implementation, the method for obtaining the transmission sequencesand modulation symbols is the same as that in Mode 2. The onlydifference is that the two obtained sequences are respectively sentthrough each antenna in this mode.

FIG. 8 is a schematic diagram showing the sending of sequences andsymbols according to another embodiment of the disclosure. Referring toFIG. 8, a first modulation symbol a1 is mapped to a first transmissionsequence Si, and sent through a first antenna; a second modulationsymbol a2 is mapped to a first transmission sequence Sj, and sentthrough a second antenna. Other implementation principles are the sameas that in Mode 2, and are not described herein again.

In Mode 4, the UE includes multiple antennas, and each antenna transmitsone of multiple received transmission sequences. The multiple sequencestransmit the same modulation symbol.

As in Mode 3, each antenna sends one sequence, thereby maintaining thesingle-carrier transmission; but the same modulation symbol is sentthrough different antennas, and in this manner, a transmission diversitygain is obtained. In an actual system, the probability that fadingoccurs to all antenna channels at the same time is very low; therefore,if severe fading occurs to one of the antenna channels, signals fromother antennas can compensate for the fading. The transmission diversitycan improve the performance of the A/N detection at the BS end. Comparedwith single-antenna transmission of the LTE system, this mode can obtainbetter A/N transmission performance, and improve the coverage area of acell. While obtaining the same performance as the single-antennatransmission, this transmission mode can reduce the transmission powerand prolong the terminal standby time of the user.

It is assumed that the system includes 2 antennas and 4 downlinkfrequency bands for transmitting data to the user, and each downlinkfrequency band includes two codewords. The PDCCH of the primary downlinkfrequency band is formed by 4 CCEs. Then 4 sequences are reserved on theprimary uplink frequency band (M=4), and the sequences are S1, S2, S3and S4 respectively. It is assumed that 2 transmission sequences need tobe selected (N=2). For the 4 downlink frequency bands, altogether 8 bitsof the A/N information exist. In this embodiment, the logic ANDoperation is performed on the two bits of A/N information in eachdownlink frequency band, and the bits corresponding to the A/Ninformation that needs to be transmitted in the downlink frequency bandis 4 (m=4). The A/N information is A/N(1), A/N(2), A/N(3) and A/N(4)respectively. The bits, of which m=4, are divided into two parts: afirst bit group [A/N(1) A/N(2)], of which m1=2, and a second bit group[A/N(3) A/N(4)], of which m2=m−m1=2. The transmission sequences whichselect N=2 in the reserved sequences are obtained according to the firstbit group [A/N (1) A/N (2)], and a modulation symbol is obtainedaccording to the second bit group [A/N (3) A/N (4)]. For therelationship between the first bit group and the transmission sequence,references can be made to Table 6. For the relationship between thesecond bit group and the modulation symbol (QPSK symbol), references canbe made to Table 5.

FIG. 9 is a schematic diagram showing the sending of sequences andsymbols according to another embodiment of the disclosure. Referring toFIG. 9, after the transmission sequences Si and Sj and a QPSK symbol areobtained through referring to Table 6 and Table 5 according to the bitsof the A/N information that needs to be transmitted, the two sequencesare sent through two antennas respectively, and the same QPSK symbolsare transmitted in the two sequences. For example, for a user, ifA/N(1)=1, A/N(2)=0, A/N(3)=1, and A/N(4)=1, the transmission sequencescorresponding to [A/N(1),A/N(2)]=[1 0] and obtained according to Table 6are (S1, S4). The QPSK modulation symbol modulated from[A/N(3),A/N(4)]=[1 1] obtained according to Table 5 is Q3. After that,the modulation symbol Q3 is mapped to the different sequences S1 and S4.Then the two transmission sequences transmitting the same modulationsymbol are sent through two antennas. After receiving the feedbacksignal, the BS performs the detection, and detects that the sequences(S1, S4) include the modulation symbol, and the modulation symbol is Q3.The BS can obtain [A/N(1) A/N(2)]=[1 0], and [A/N(3) A/N(4)]=[1 1]according to the mapping relationship between the transmission sequenceand the modulation symbol, and of Table 6 and Table 5. When the A/N is1, it indicates the correct transmission; when the A/N is 0, itindicates the incorrect transmission. Besides, during the negotiationwith the terminal, the BS knows in advance that A/N(1), A/N(2), A/N(3)and A/N(4) respectively correspond to a first downlink frequency band, asecond downlink frequency band, a third downlink frequency band, and afourth downlink frequency band. Therefore, the BS knows whether codewords of the second downlink frequency band are transmitted correctly.The BS can re-transmit the code words of the second downlink frequencyband only, and does not need to re-transmit code words of all thefrequency bands.

For example, in yet another embodiment, 5 downlink frequency bandstransmit data to the user, and each downlink frequency band has twocodewords. The PDCCH in the main downlink frequency band is formed by 8CCEs. Then 8 sequences (M=8) are reserved in the primary uplinkfrequency band, which are S1, S2, S3, S4, S5, S6, S7 and S8respectively. For 5 downlink frequency bands, 10 bits of A/N exist. Ifthe logic AND operation is performed on the two A/Ns of each downlinkfrequency band, 5 A/Ns (m=5) are obtained, which are A/N(1), A/N(2),A/N(3), A/N(4) and A/N(5) respectively, and need to be sent to the BS.The 5 bits (m=5) of A/Ns are divided into two groups. Group 1 is [A/N(1)A/N(2) A/N(3)], of which m1=3, and is used for selecting 2 sequences(N=2) Si and Sj from 8 sequences. The relationship of sequence selectionis shown in Table 7. Group 2 is [A/N(4) and A/N(5)], of which m2=2, andis used for forming a QPSK modulation symbol; the modulation mapping isshown in Table 5.

TABLE 7 A/N (1) A/N (2) A/N (3) (S1, S2) (S3, S4) (S5, S6) (S7, S8) 000✓ 001 ✓ 010 ✓ 011 ✓ A/N (1) A/N (2) A/N (3) (S1, S3) (S2, S4) (S5, S7)(S6, S8) 100 ✓ 101 ✓ 110 ✓ 111 ✓

If the user has two sending antennas, each antenna sends one sequence,and the two sequences send the same QPSK modulation symbol, as shown inFIG. 9.

For the user, if A/N(1)=0, A/N(2)=1, A/N(3)=1, A/N(4)=0, and A/N(5)=1,then [A/N(1) A/N(2) A/N(3)]=[0 1 1], where [A/N(1) A/N(2) A/N(3)] isused for selecting the sequence; the two sequences selected according toTable 7 are (S7, S8); and [A/N(4) A/N(5)]=[0 1] is modulated to Q1. Thenthe Q1 is sent through two antennas through the sequences S7 and S8respectively. Since the same signal is sent through two antennas, thetransmission diversity can be obtained.

After receiving the feedback signal, the BS performs the detection. Ifit is detected that the sequences used are (S7, S8), it can be obtainedthat [A/N(1) A/N(2) A/N(3)]=[0 1 1]; and if it is detected that the QPSKsymbol transmitted on the sequences is Q1, it can be obtained that[A/N(4) A/N(5)]=[0 1]. During the negotiation with the terminal, the BSknows in advance that the A/N(1), A/N(2), A/N(3), A/N(4) and A/N(5)respectively correspond to a first downlink frequency band, a seconddownlink frequency band, a third downlink frequency band, a fourthdownlink frequency band, and a fifth downlink frequency band. Then theBS knows that data in the first downlink frequency band and the fourthfrequency band is transmitted incorrectly, and the other data istransmitted correctly. Only two code words of the first frequency bandand two code words of the fourth frequency band need to bere-transmitted, and the data of each frequency band does not need to betransmitted.

In Mode 5, the UE has multiple antennas, and the multiple antennastransmit multiple sequences, where at least one antenna transmits atleast two transmission sequences. Modulation symbols transmitted inmultiple sequences transmitted through one antenna are different.

FIG. 10 is a schematic diagram showing the sending of sequences andsymbols according to another embodiment of the disclosure. Referring toFIG. 10, it is assumed that the system includes two antennas (a firstantenna and a second antenna); the number of transmission sequences thatneed to be selected is 3, which are Si, Sj and Sk respectively. Si andSj are transmitted through the same antenna. The modulation symbolscorresponding to Si and Sj are a1 and a2 respectively. The modulationsymbol corresponding to Sk is a, where a1 is different from a2, and acan be the same as one of a1 and a2, or be different from both. The modefor obtaining a1, a2, Si and Sj, and transmitting a1, a2, Si and Sjthrough one antenna can be referred to Mode 2; the mode for obtaining aand Sk, and transmitting a and Sk through one antenna can be referred toMode 1.

For example, 4 downlink frequency bands transmit data to the user, andeach downlink frequency band includes two codewords. The PDCCH of theprimary downlink frequency band is formed by 4 CCEs. Then 4 sequences(M=4) are reserved on the primary uplink frequency band, which arerespectively Si, S2, S3 and S4. It is assumed that the number of thetransmission sequences that need to be selected is 3 (N=3). For the 4downlink frequency bands, 8 bits of A/N information (m=8) exist, whichare A/N(1), A/N(2), A/N(3), A/N(4), A/N(5), A/N(6), A/N(7) and A/N(8)respectively. The bits, of which m=8, are divided into two parts: afirst bit group [A/N(1) A/N(2)], of which m1=2, and a second bit group[A/N(3) A/N(4) A/N(5) A/N(6) A/N(7) A/N(8)], of which m2=m−m1=6. Thetransmission sequences which select N=3 in the reserved sequences areobtained according to the first bit group [A/N (1) A/N (2)], and threemodulation symbols are obtained according to [A/N (3) A/N (4)], [A/N(5)A/N(6)], and [A/N(7) A/N(8)] of the second bit group. For therelationship between the first bit group and the transmission sequence,references can be made to Table 8; for the relationship between thesecond bit group and the modulation symbol (QPSK symbol), references canbe made to Table 5.

TABLE 8 (S2, S3, A/N (1) A/N (2) (S1, S2, S3) (S1, S2, S4) (S1, S3, S4)S4) 00 ✓ 01 ✓ 10 ✓ 11 ✓

For a user, if A/N(1)=1, A/N(2)=0, A/N(3)=1, A/N(4)=1, A/N(5)=1,A/N(6)=0, A/N(7)=0, and A/N(8)=1, then the transmission sequencescorresponding to [A/N(1), A/N(2)]=[0 1] obtained according to Table 8are (S1, S3, S4). The first QPSK modulation symbol a1 obtained accordingto Table 5 which is modulated from [A/N(3), A/N(4)]=[1 0] is Q3. Thesecond QPSK modulation symbol a2 modulated from [A/N(5), A/N(6)]=[1 0]is Q2. The third QPSK modulation symbol a3 modulated from [A/N(7),A/N(8)]=[0 1] is Q1. After that, the first modulation symbol Q3 ismapped to a first sequence S1, and the second modulation symbol Q2 ismapped to a second sequence S3. The first sequence Si and the secondsequence S3 are added and sent through the same antenna. The thirdmodulation symbol Q1 is mapped to a third sequence S4, and the thirdsequence S4 is sent through another antenna. After receiving thefeedback signal, the BS performs the detection, and detects that thesequences (Si, S3, S4) include the modulation symbols. The modulationsymbols are Q3, Q2 and Q1 respectively. The BS can obtain that [A/N(1)A/N(2)]=[1 0], [A/N(3) A/N(4)]=[1 1], [A/N(5),A/N(6)]=[1 0], and[A/N(7),A/N(8)]=[0 1] according to the corresponding relationshipbetween the transmission sequence and the modulation symbol, and ofTable 8 and Table 5. When the A/N is 1, it indicates the correcttransmission, and when the A/N is 0, it indicates the incorrecttransmission. Besides, during negotiation with the terminal, the BSknows in advance that A/N(1), A/N(2), A/N(3), A/N(4), A/N(5), A/N(4),A/N(5), A/N(6), A/N(7) and A/N(8) respectively correspond to a firstcode word of a first downlink frequency band, a second code word of thefirst downlink frequency band, a first code word of a second downlinkfrequency band, a second code word of the second downlink frequencyband, a first code word of a third downlink frequency band, a secondcode word of the third downlink frequency band, a first code word of afourth downlink frequency band, and a second code word of the fourthdownlink frequency band. Therefore, the BS can know that the second codeword of the first downlink frequency band, the second code word of thethird downlink frequency band, and the first code word of the fourthdownlink frequency band are transmitted incorrectly. The BS canre-transmit the first code word of the second downlink frequency band,the second code word of the third downlink frequency band, and the firstcode word of the fourth downlink frequency band only, and does not needto re-transmit all code words of all frequency bands.

The above modes of selecting m1 and m2 are merely examples. Personsskilled in the art can have other combinations based on the aboveprinciples and specific values of M and N. Moreover, the QPSK modulationsymbol is used as an example in the above embodiment; the BPSKmodulation symbol or a modulation symbol of other modulation orders mayalso be obtained from the A/N bits.

The reserved resources in the above embodiments are determined by theCCEs of the PDCCH corresponding to each user in the primary downlinkfrequency band of the user. Apart from that, another possibility is thatthe user has the PDCCH in each downlink frequency band; then the A/Nresources transmitted on the primary uplink frequency band may also bedetermined by all PDCCHs. FIG. 11 is a schematic diagram of a mappingrelationship between an uplink and a downlink according to anotherembodiment of the disclosure. Referring to FIG. 11, for example, aPDCCH1 in a frequency band 1 is formed by 2 CCEs; and a PDCCH2 in afrequency band 2 is formed by 2 CCEs; then two sequences are reserved inthe uplink frequency band for the PDCCH1 and the PDCCH2 respectively,that is, M1=1, and M2=2. Therefore, 4 sequences (M=4) are reserved inthe main uplink frequency band. That is to say, the reserved resourcesare determined according to the CCEs included in the PDCCHs of all thedownlink frequency bands corresponding to the user. The number of CCEsincluded in the PDCCHs of all the downlink frequency bands is used asthe number of the reserved resources. After that, the processing methodmay be any one of the preceding Mode 1 to Mode 5.

For example, 2 downlink frequency bands transmit data to the user, andeach downlink frequency band has two codewords. The PDCCH1 of thefrequency band 1 is formed by 2 CCEs, and the PDCCH2 of the frequencyband 2 is formed by 2 CCEs. Then two sequences are reserved in theuplink frequency band for the PDCCH1 and the PDCCH2 respectively, thatis, M1=1, and M2=2. Therefore, 4 sequences (M=M1+M2=4) are reserved inthe primary uplink frequency band, which are Si, S2, S3 and S4respectively. It is assumed that the 2 transmission sequences (N=2) needto be selected. For the 2 downlink frequency bands, the number of bitsof the A/N information that needs to be transmitted is 4 (m=4), and theA/N information is A/N (1), A/N (2), A/N (3) and A/N (4) respectively.The 4 bits of the A/N information are all assigned to the first bitgroup, and the second bit group is empty. The sequences and themodulation symbols are jointly selected according to the 4 bits of A/Ninformation in the first bit group.

TABLE 9 A/N(1)A/N(2)A/N(3) A/N(4) Sequence Modulation symbol 0000 (S1,S2) $Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0001 (S2, S3)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0010 (S3, S4)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0011 (S1, S4)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0100 (S1, S2)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 0101 (S2, S3)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 0110 (S3, S4)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 0111 (S1, S4)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 1111 (S1, S2)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1000 (S2, S3)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1110 (S3, S4)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1011 (S1, S4)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ 1001 (S1, S2)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1100 (S2, S3)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1010 (S3, S4)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1101 (S1, S4)$Q_{1} = \frac{1 - j}{\sqrt{2}}$

Then the two transmission sequences and modulation symbols are sentthrough two antennas according to a manner of Mode 4.

If the UE knows the number of the PDCCHs transmitted by the BS in thedownlink, and does not correctly detect all the PDCCHs, a DTX needs tobe returned. A DTX state affects the way that the transmission sequencesare selected in the reserved sequences. Since the reserved resourcesdetermined by the UE does not include the reserved resourcescorresponding to the PDCCHs in accordance with the DTX, the UE can onlyselect the transmission sequences from the reserved resourcescorresponding to the PDCCHs that are correctly detected. For example, 2downlink frequency bands transmit data and PDCCHs to the user, and eachdownlink frequency band has one codeword. The PDCCH1 of the frequencyband 1 is formed by 2 CCEs (corresponding to the uplink sequences S1 andS2), and the PDCCH2 of the frequency band 2 is formed by 2 CCEs(corresponding to the uplink sequences S3 and S4). If both PDCCH1 andPDCCH 2 are correctly detected by the UE, the reserved resourcesdetermined by the UE in the uplink frequency bands are 51, S2, S3, andS4. If only the PDCCH1 is correctly detected, the reserved resourcesdetermined by the UE in the uplink frequency band are Si and S2.Alternatively, if only the PDCCH2 is correctly detected, the reservedresources determined by the UE in the uplink frequency band are S3 andS4.

If the UE knows that the BS transmits two PDCCHs, and each PDCCHcorresponds to one data block, the UE returns for the two data blocks,regardless of whether the PDCCHs are correctly detected or not. In thisway, the DTX state exists. For example, feedback for the data blockcorresponding to the PDCCH1 is ACK, and the feedback for the data blockcorresponding to PDCCH2 is DTX; then the transmission sequences can onlybe Si or/and S2 (determined by the required number of transmissionsequences). The sequence selection can be expressed through Table 10below.

TABLE 10 A/N(1)A/N(2) Sequence Modulation symbol 0 0 (S1, S2)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0 1 (S3, S4)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1 0 (S1, S2)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ 1 1 (S3, S4)$Q_{0} = \frac{1 + j}{\sqrt{2}}$ 0 DTX (S1, S2)$Q_{1} = \frac{1 - j}{\sqrt{2}}$ 1 DTX (S1, S2)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ DTX 0 (S3, S4)$Q_{2} = \frac{{- 1} + j}{\sqrt{2}}$ DTX 1 (S3, S4)$Q_{3} = \frac{{- 1} - j}{\sqrt{2}}$ DTX DTX NA NA

Then the two transmission sequences and modulation symbols are sentthrough two antennas according to a manner of Mode 4.

In addition, the preceding illustration and embodiments are all based onthe assumption that the reserved resources are in the primary uplinkfrequency band. Besides, the reserved resources may also be in multipleuplink frequency bands. For a certain user, if three downlink frequencybands exist in the downlink, and two uplink frequency bands exist in theuplink, M1 and M2 resources are reserved in each uplink frequency bandrespectively, and the user altogether reserves (M1+M2) resources. Thetransmission resources for transmitting the A/N of the user may beselected from the reserved (M1+M2) resources.

Moreover, the above embodiments are all based on the assumption that thereserved resources are indirectly obtained through the PDCCHs in theprimary downlink frequency band or multiple downlink frequency bands;however, the reserved resources may also be assigned through theexplicit signaling, or jointly obtained through the indirect PDCCHs andthe explicit signaling.

In the embodiments of the disclosure, the bits of the A/N informationthat needs to be transmitted are divided into the first bit group andthe second bit group. The transmission resources are obtained accordingto the first bit group, and the corresponding modulation symbols areobtained according to the second bit group, so that the BS can determinewhether each data block is transmitted correctly or not.

Specifically, further, the second bit group can be empty; thetransmission resources and the modulation symbols can be obtainedthrough the first bit group only.

Persons of ordinary skill in the art should understand that, all or apart of the steps of the method according to the embodiments may beimplemented by a program instructing relevant hardware. The program maybe stored in a computer readable storage medium. When the program isexecuted, the steps of the method according to the embodiments areperformed. The storage medium may be any medium capable of storingprogram codes, such as a read-only memory (ROM), a random access memory(RAM), a magnetic disk or an optical disk.

FIG. 12 is a schematic structure diagram of a UE according to anotherembodiment of the disclosure. The UE includes a first determinationmodule 121, a second determination module 122, a grouping module 123, anobtaining module 124 and a transmission module 125. The firstdetermination module 121 is configured to determine reserved resources.The second determination module is configured to determine A/Ninformation that needs to be transmitted. The grouping module 123 isconnected to the first determination module 121 and the seconddetermination module 122, and is configured to divide the A/Ninformation that needs to be transmitted into a first bit group and asecond bit group according to the number of the reserved resources, anddetermine that the number of transmission resources is N. The obtainingmodule 124 is connected to the grouping module 123, and is configured toobtain the N transmission resources from the reserved resourcesaccording to the first bit group, and obtain corresponding modulationsymbols according to the second bit group. The transmission module 125is connected to the grouping module 123 and the obtaining module 124,and is configured to transmit the obtained modulation symbols by usingthe obtained transmission resources. The number of bits of the first bitgroup obtained by the grouping module 123 is m1, which needs to meet2^(m1)≦C_(M) ^(N), where M is the number of the reserved resources, andN is the number of the transmission resources.

Specifically, further, the second bit group can be empty; the Ntransmission resources and the modulation symbols can be obtainedthrough the first bit group only. That is to say, the obtaining module124 obtains N transmission resources and the corresponding modulationsymbols from the reserved resources according to the first bit group.

In this embodiment, the bits of the A/N information that needs to betransmitted are divided into the first bit group and the second bitgroup. The transmission resources are obtained according to the firstbit group, and the modulation symbols are obtained according to thesecond bit group, so that each bit can affect the information in theuplink frequency band; therefore BS can determine whether each datablock is transmitted correctly.

Specifically, the second bit group can be empty; the transmissionresources and the modulation symbols can be obtained through the firstbit group only.

Finally, it should be noted that the above embodiments are merelyprovided for describing the technical solutions of the disclosure, butnot intended to limit the present application. It should be understoodby persons of ordinary skill in the art that although the disclosure hasbeen described in detail with reference to the embodiments,modifications or equivalent replacements can still be made to thetechnical solutions of the present application, as long as suchmodifications or replacements do not depart from the spirit and scope ofthe present application.

What is claimed is:
 1. A method, comprising: receiving, by a terminaldevice, at least one data block via at least one of at least twodownlink frequency bands; determining, by the terminal device,acknowledgement/negative acknowledgement (A/N) information, wherein theA/N information indicates whether the at least one data block iscorrectly detected by the terminal device; determining, by the terminaldevice, a modulation symbol and a transmission resource according to theA/N information in accordance, wherein the A/N information iscorresponding to the modulation symbol and the transmission resource;and transmitting, by the terminal device, the modulation symbol on thetransmission resource via N antenna ports, wherein N is an integergreater than or equal to
 2. 2. The method of claim 1, furthercomprising: receiving control information relating to the at least onedata block to the UE, the control information being transmitted via aphysical downlink control channel (PDCCH).
 3. The method of claim 1,wherein each of the N antenna ports corresponds to one spreadingsequence, and each of N spreading sequences is a two-dimensionalspreading code.
 4. The method of claim 3, wherein each of thetwo-dimensional spreading sequences is an orthogonal two-dimensionalspreading code.
 5. The method of claim 1, wherein the modulation symbolis a quadrature phase shift keying (QPSK) modulation symbol.
 6. Themethod of claim 1, wherein a quantity of states of the A/N informationis related to a quantity of the at least two downlink frequency bands.7. The method of claim 8, wherein the quantity of information bits ofthe A/N information is two, three or four, and the quantity of the atleast two downlink frequency bands is two.
 8. The method of claim 1,wherein the at least one data block includes four codewords, the atleast two downlink frequency bands include two downlink frequency bands,and each of the two downlink frequency bands is capable of transmittingtwo of the four codewords.
 9. A terminal device, comprising: a receiver,a transmitter, and a processor, wherein the receiver is configured toreceive at least one data block via at least one of at least twodownlink frequency bands; the processor is configured to determineacknowledgement/negative acknowledgement (A/N) information, wherein theA/N information indicates whether the at least one data block iscorrectly detected; the processor is configured to determine amodulation symbol and a transmission resource according to the A/Ninformation in accordance, wherein the A/N information is correspondingto the modulation symbol and the transmission resource; and thetransmitter is configured to transmit the modulation symbol on thetransmission resource via N antenna ports, wherein N is an integergreater than or equal to
 2. 10. The terminal device of claim 1, whereinthe receiver is further configured to receive control informationrelating to the at least one data block to the UE, the controlinformation being transmitted via a physical downlink control channel(PDCCH).
 11. The terminal device of claim 9, wherein each of the Nantenna ports corresponds to one spreading sequence, and each of Nspreading sequences is a two-dimensional spreading code.
 12. Theterminal device of claim 11, wherein each of the two-dimensionalspreading sequences is an orthogonal two-dimensional spreading code. 13.The terminal device of claim 9, wherein the modulation symbol is aquadrature phase shift keying (QPSK) modulation symbol.
 14. The terminaldevice of claim 9, wherein a quantity of states of the A/N informationis related to a quantity of the at least two downlink frequency bands.15. The terminal device of claim 14, wherein the quantity of informationbits of the A/N information is two, three or four, and the quantity ofthe at least two downlink frequency bands is two.
 16. The terminaldevice of claim 9, wherein the at least one data block includes fourcodewords, the at least two downlink frequency bands include twodownlink frequency bands, and each of the two downlink frequency bandsis capable of transmitting two of the four codewords.
 17. An apparatus,comprising: a storage medium including executable instructions; and aprocessor; wherein the executable instructions, when executed by theprocessor, cause the apparatus to: detect at least one data block via atleast one of at least two downlink frequency bands; determineacknowledgement/negative acknowledgement (A/N) information, wherein theA/N information indicates whether the at least one data block iscorrectly detected; determine a modulation symbol and a transmissionresource according to the A/N information in accordance, wherein the A/Ninformation is corresponding to the modulation symbol and thetransmission resource; and transmit, via a transmitter of a terminaldevice, the modulation symbol on the transmission resource via N antennaports of the terminal device, wherein N is an integer greater than orequal to
 2. 18. The apparatus of claim 17, wherein each of the N antennaports corresponds to one spreading sequence, and each of N spreadingsequences is a two-dimensional spreading code.
 19. The apparatus ofclaim 18, wherein each of the two-dimensional spreading sequences is anorthogonal two-dimensional spreading code.
 20. The apparatus of claim19, wherein the modulation symbol is a quadrature phase shift keying(QPSK) modulation symbol.